SummaryPhagocytosis by cells of the innate immune system, such as macrophages, and the subsequent successful maturation of the phagosome, is key for the clearance of pathogens. The fungal pathogen Cryptococcus neoformans is known to overcome killing by host phagocytes and both replicate within these cells and also escape via a non-lytic process termed vomocytosis. Here we demonstrate that, during intracellular growth, cryptococci modify phagolysosome maturation. Live cryptococci, but not heat-killed pathogens or inert targets, induce the premature removal of the early phagosome markers Rab5 and Rab11. In addition, significant acidification of the phagosome, calcium flux and protease activity is hindered, thus rendering the phagosome permissive for cryptococcal proliferation. Interestingly, several attenuated cryptococcal mutants retain this ability to subvert phagosomal maturation, suggesting that hitherto unidentified pathogen mechanisms regulate this process.
SummaryQuorum sensing was once considered a way in which a species was able to sense its cell density and regulate gene expression accordingly. However, it is now becoming apparent that multiple microbes can sense particular quorum‐sensing molecules, enabling them to sense and respond to other microbes in their neighbourhood. Such interactions are significant within the context of polymicrobial disease, in which the competition or cooperation of microbes can alter disease progression. Fungi comprise a small but important component of the human microbiome and are in constant contact with bacteria and viruses. The discovery of quorum‐sensing pathways in fungi has led to the characterization of a number of interkingdom quorum‐sensing interactions. Here, we review the recent developments in quorum sensing in medically important fungi, and the implications these interactions have on the host's innate immune response.
Background Mother-to-baby transmission of group B Streptococcus (Streptococcus agalactiae) is the main cause of early-onset infection. Objectives We investigated if intrapartum antibiotic prophylaxis directed by a rapid intrapartum test reduces maternal and neonatal antibiotic use, compared with usual care (i.e. risk factor-directed antibiotics), among women with risk factors for vertical group B Streptococcus transmission, and examined the accuracy and cost-effectiveness of the rapid test. Design An unblinded cluster randomised controlled trial with a nested test accuracy study, an economic evaluation and a microbiology substudy. Setting UK maternity units were randomised to either a strategy of rapid test or usual care. Participants Vaginal and rectal swabs were taken from women with risk factors for vertical group B Streptococcus transmission in established term labour. The accuracy of the GeneXpert® Dx IV GBS rapid testing system (Cepheid, Maurens-Scopont, France) was compared with the standard of selective enrichment culture in diagnosing maternal group B Streptococcus colonisation. Main outcome measures Primary outcomes were rates of intrapartum antibiotic prophylaxis administered to prevent early-onset group B Streptococcus infection and accuracy estimates of the rapid test. Secondary outcomes were maternal antibiotics for any indication, neonatal antibiotic exposure, maternal antibiotic duration, neonatal group B Streptococcus colonisation, maternal and neonatal antibiotic resistance, neonatal morbidity and mortality, and cost-effectiveness of the strategies. Results Twenty-two maternity units were randomised and 20 were recruited. A total of 722 mothers (749 babies) participated in rapid test units and 906 mothers (951 babies) participated in usual-care units. There were no differences in the rates of intrapartum antibiotic prophylaxis for preventing early-onset group B Streptococcus infection in the rapid test units (41%, 297/716) compared with the usual-care units (36%, 328/906) (risk ratio 1.16, 95% confidence interval 0.83 to 1.64). There were no differences between the groups in intrapartum antibiotic administration for any indication (risk ratio 0.99, 95% confidence interval 0.81 to 1.21). Babies born in the rapid test units were 29% less likely to receive antibiotics (risk ratio 0.71, 95% confidence interval 0.54 to 0.95) than those born in usual-care units. The sensitivity and specificity of the rapid test were 86% (95% confidence interval 81% to 91%) and 89% (95% confidence interval 85% to 92%), respectively. In 14% of women (99/710), the rapid test was invalid or the machine failed to provide a result. In the economic analysis, the rapid test was shown to be both less effective and more costly and, therefore, dominated by usual care. Sensitivity analysis indicated potential lower costs for the rapid test strategy when neonatal costs were included. No serious adverse events were reported. Conclusions The Group B Streptococcus 2 (GBS2) trial found no evidence that the rapid test reduces the rates of intrapartum antibiotic prophylaxis administered to prevent early-onset group B Streptococcus infection. The rapid test has the potential to reduce neonatal exposure to antibiotics, but economically is dominated by usual care. The accuracy of the test is within acceptable limits. Future work The role of routine testing for prevention of neonatal infection requires evaluation in a randomised controlled trial. Trial registration Current Controlled Trials ISRCTN74746075. Funding This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 12. See the NIHR Journals Library website for further project information.
Background People experiencing homelessness (PEH) have complex health and social care needs and most die in their early 40 s. PEH frequently use community pharmacies; however, evaluation of the delivery of structured, integrated, holistic health and social care intervention has not been previously undertaken in community pharmacies for PEH. PHOENIx (Pharmacy Homeless Outreach Engagement Non-medical Independent prescribing Rx) has been delivered and tested in Glasgow, Scotland, by NHS pharmacist independent prescribers and third sector homelessness support workers offering health and social care intervention in low threshold homeless drop-in venues, emergency accommodation and emergency departments, to PEH. Building on this work, this study aims to test recruitment, retention, intervention adherence and fidelity of community pharmacy-based PHOENIx intervention. Methods Randomised, multi-centre, open, parallel-group external pilot trial. A total of 100 PEH aged 18 years and over will be recruited from community pharmacies in Glasgow and Birmingham. PHOENIx intervention includes structured assessment in the community pharmacy of health, housing, benefits and activities, in addition to usual care, through weekly visits lasting up to six months. A primary outcome is whether to proceed to a definitive trial based on pre-specified progression criteria. Secondary outcomes include drug/alcohol treatment uptake and treatment retention; overdose rates; mortality and time to death; prison/criminal justice encounters; healthcare utilisation; housing tenure; patient-reported measures and intervention acceptability. Analysis will include descriptive statistics of recruitment and retention rates. Process evaluation will be conducted using Normalisation Process Theory. Health, social care and personal resource use data will be identified, measured and valued. Discussion If the findings of this pilot study suggest progression to a definitive trial, and if the definitive trial offers positive outcomes, it is intended that PHOENIx will be a publicly funded free-to-access service in community pharmacy for PEH. The study results will be shared with wider stakeholders and patients in addition to dissemination through medical journals and scientific conferences. Trial registration International Clinical Trial Registration ISRCTN88146807. Approved protocol version 2.0 dated July 19, 2022.
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